Archive for February 2019

The U.S. Army's M25 Stabilized Binocular

Complex solutions to a simple problem

When I got married, my wife gave me a wonderful wedding present: a pair of binoculars. I don’t recall ever having said, “I sure wish I had binoculars,” but I couldn’t have been more delighted at her choice. I remember having two distinct thoughts about the gift: first, that this woman must know me awfully well to discern that this is the kind of thing I’d think is not merely cool, but perfectly appropriate as a wedding present; and second, that I now had the ability to see things at a distance. This latter point is not as trivial as it sounds. I have pretty good eyesight, but whether I’m at a concert or play, or on a street corner in a strange city trying to get my bearings, it seems that I’m always about 20 meters too far away to make out the significant details of whatever I’m looking at. For some reason, it had never seriously occurred to me to solve this problem by investing in a pair of binoculars, but now that I unexpectedly had the ability to see things farther away than normal, I found myself excited by the possibilities it would open up.

I am not exactly the target audience for most binoculars—which is to say, I’m not into hunting, boating, bird watching, professional sports, amateur astronomy, or voyeurism. That said, I do find it quite handy to be able to get a closer look at a variety of things on occasion, and looking through binoculars has the curious effect of always making me wish I could see just a little closer still. In other words, if the binoculars reveal that the blur in the distance is in fact a bus, I inevitably wish they magnified the image slightly more so that I could read the number that would tell me if it’s the bus I’m waiting for. Unfortunately, if my wife had bought me binoculars with higher magnification, it actually would have worked against me. The facts of geometry being what they are, small hand movements are amplified dramatically when you’re looking at something far away, so that in most cases, magnifications of greater than about 8x require a tripod to steady the binoculars if they’re going to be useful.

Holding Steady

This problem did not go unnoticed by the military and the space program, both of which had excellent reasons for needing high magnification, and both of which tended to use binoculars in intrinsically unstable locations where a tripod wouldn’t have done much good—on a rocking boat, a moving truck, or a spacecraft, for instance. And so a solution was developed, in typical military style: robust, but heavy, expensive, and awkward. The solution was basically to outfit the binoculars with a gyroscope, whose centrifugal force kept the entire unit relatively steady. Although this did in fact provide a more stable image at greater magnifications, it added significant bulk and weight, used a lot of power, and also required a bit of time for the gyroscope to spin up before the image steadied.

Meanwhile, an entirely different industry was working on a solution to a similar problem. As consumer video cameras became smaller and lighter and turned into camcorders, and as camcorders acquired ever-longer zoom lenses, it became increasingly difficult to create quality home movies of things far away using a handheld device. Clearly, consumers who want a lightweight, pocket-sized device are not going to accept a gyroscope any more than bouncy images, so a different tactic was needed.

You might be thinking: big deal; my smartphone has been able to do this for a long time. Sure, but between your smartphone’s camera and digital display is a fancy microprocessor, along with software that can digitally compensate for shaking in real time. Since binoculars are (generally) optical, not digital, those tricks can’t be used. So how do they do it in purely optical devices?

Let’s Do the Twist

The innovation camcorder makers came up with was this: instead of stabilizing the entire device, simply stabilize the portion of the optical system inside that actually mattered. A number of different and clever solutions to this problem were developed and later modified further so they could be applied to binoculars as well. The result is that several different manufacturers now make high-power binoculars that will give you, at the touch of a button, a frighteningly rock-solid image.

One approach was simply to shrink down the gyroscopes that had been used to steady the entire binoculars of early designs, and use them just to steady the prisms (the parts of the optical path that flip over the image so that it’s right-side-up). This is reasonably effective, but still requires a fair amount of power and adds considerable bulk and weight. This method is used by Russian brands Peleng and SIB. Fujinon uses a variation on this approach, which instead of stabilizing the prisms directly with gyroscopes, incorporates much smaller gyros along with solid-state vibration sensors to feed data to a microprocessor, which then directs tiny motors to reposition the prisms.

An even higher-tech approach by Canon does away with gyroscopes altogether. Early Canon models used a set of motion-sensing devices called accelerometers to measure the unit’s movement, and then handed the data to a microprocessor that determines whether it was intentional movement or not; based on the processor’s decision, it adjusted the angle of the glass faces on a unique, water-filled flexible prism. Later Canon designs instead adjust the angle of a single element within the lens barrel on each side, which has the same effect but requires less power, size, and weight.

All of these approaches, while roughly equal in effectiveness, still require batteries, which may last as little as two to six hours in constant use. An alternative design is all-mechanical. It basically mounts weighted prisms in a special gimbal—a mechanical assembly that allows them to tilt freely in any direction—without any help from gyroscopes, motors, or microprocessors. Carl Zeiss stabilizing binoculars use this approach.

The Cost of Stability

Image-stabilizing binoculars (also known as “image stabilization” or “image stabilized” binoculars) can give you a steadier image at up to 20x magnification than ordinary binoculars will give you at 7 or 8x. But this marvelous technology doesn’t come cheap. A quick survey of a number of different models showed prices ranging from as little as US$300 for an 8x Canon model to $9,000 for a top-of-the-line 20x Zeiss. They are also, without exception, quite a bit heavier than their conventional counterparts—regardless of which technology they use. But apart from their obvious utility to lovers of nature, sports, or live music, they are just plain cool. When I tried a couple of models out in a store, I was simply amazed at the nearly magical effect. Alas, my gadget budget cannot currently accommodate such a luxury, but give me a nice solid 16x model with a built-in compass, rangefinder, night vision, and hi-res digital camera for about $500 and I’ll be happy to hand over the plastic. I’m sure it’s only a matter of time.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on June 6, 2003, and again in a slightly revised form on November 9, 2004.

Image credit: Program Executive Office Soldier [CC BY 2.0], via Flickr


Source: Interesting Thing of the Day

Random acts of kindness sign

This is what the world has come to: the best we can seem to manage is a hope, a wish, a plea that just one day a year some small percentage of us will be nice to other people without expecting anything in return. Well, I guess it’s a start. Be kind to someone, or better yet, several someones today. See how it goes. Remember how it feels. And you know what, you are totally allowed to do the same thing again tomorrow. Honest! The kindness police will not cite you for being nice on other days of the year. And if it turns into a habit, well, there are much worse habits.

Image credit: Heath Brandon [CC BY-SA 2.0], via Flickr


Source: Interesting Thing of the Day

Salzbergwerk Berchtesgaden

Mining salt in Bavaria

Nowadays, we take salt for granted. Sold for a pittance, the most common of spices, we think of it as an everyday thing, when we think of it at all. It wasn’t always so. In fact, great empires and fortunes rose and fell according to its supply. It is hard to imagine a modern war being fought over salt. But consider these historical events, as recounted in Margaret Visser’s Much Depends on Dinner:

Morocco fought Mali in the sixteenth century for the mines of Taoudeni; the Venetians, whose salt interests are an historical study in themselves, destroyed Comacchio in the tenth century and the salt gardens of Cervia in the fourteenth; pirates throughout the centuries ambushed and raided the slow heavy convoys of salt ships.

There are plenty of other examples—all of which seem outlandish to us today, considering that the biggest battles fought over salt have to do with whether it should be spread over icy roads in winter. Salt has lost its nobility, its historical power—but from the salt-starved Vikings to the salt-greedy Romans, salt has played an important role in human history.

The Saltman Cometh

Nowhere does this seem more obvious than in the salt-rich environs of eastern Bavaria and western Austria. The de facto capital of the region, Salzburg (or “salt town”) was built by its first archbishop in the eighth century with profits from salt mining, but the practice of salt mining goes back even further, to the civilization of the early Celts. In his book Salt: A World History, Mark Kurlansky describes the discovery by local salt miners in the 1600s of a “perfectly preserved body, dried and salted ‘like codfish,’” believed now to date to 400 BCE. Dressed in colorful fabrics, this “saltman” and two others like him were found with the tools of their trade near them, proof of an ancient salt mining culture.

Salt of the Earth

This salt mining tradition continues in the modern salt works along the German/Austrian border, and it’s possible to experience some of what those ancient miners might have felt, deep in the mountains of salt. Founded in 1517, the Salzbergwerk Berchtesgaden (“Berchtesgaden salt mine”)—located near Salzburg but on the German side of the border—once entertained only aristocratic visitors, but now welcomes the public to its underground facilities and caves. Berchtesgaden, linked in the public imagination with Hitler’s southern headquarters (although they were actually located at Obersalzberg, a small settlement further up in the mountains) is a town that developed in proximity to the Augustinian monastery that owned the Salzbergwerk. In the early 1800s the monastery was converted into a palace for the Wittelsbachs, rulers of Bavaria at the time, and the entire area became associated with this colorful family.

Mine Games

Still operational, the Salzbergwerk is a fascinating place to visit. When I was there years ago, we were given the traditional leather vests and helmets of the miners to wear (now visitors sport sturdy coveralls), making you feel as if you are a miner yourself. This sensation is heightened when, after a short train ride, you are asked to slide down a wooden chute into the mine itself, just as the miners would do.

The most memorable part of the tour for me was gliding across a large underground lake on a wooden platform boat, an experience that was both beautiful and eerie. I was wowed by the size of the lake, and also slightly disconcerted by the oppressive nearness of the stone “ceiling.” It was definitely not something you see everyday, unless you happen to be a Bavarian salt miner.

Worth Its Salt

Returning from the depths of the mine, it was hard to think of salt the same way again. It is, after all, the only rock that we eat, and with thousands of tons of it looming above your head, you don’t immediately think, “pass the salt.” Vital to the functioning of our vital organs, we would die without salt, yet we live in a salt-glutted world, so much so that we are told to reduce our intake, for the sake of our health.

In their song “NaCl (Sodium Chloride),” folk singers Kate and Anna McGarrigle make a case for the worthiness of salt. Describing the meeting, mating and melding of a sodium atom and a chlorine atom in the primordial sea, they ask us to “Think of the love that you eat, when you salt your meat.” Silly, meant to be taken with a “grain of salt,” yet it expresses the mystery of salt, the serendipitous compound that protects our cells, and fills the ocean.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on August 28, 2003, and again in a slightly revised form on November 28, 2004.


Source: Interesting Thing of the Day

Roasted almonds

Almonds are, without a doubt, my favorite tree nut. I eat at least a few almost every day. I think I’ll eat more than a few today, since it’s National Almond Day. I’ve read that my home state of California produces about 80% of the nation’s almonds, and nearly half of all almonds in the world. You’re welcome. Almonds are rich in nutrients and high in fiber, making them (in moderation) a good part of a balanced diet. (Almonds covered in dark chocolate are pretty much the food of the gods.) Enjoy a handful today!

Image credit: Pxhere


Source: Interesting Thing of the Day

House 8 of Skara Brae

House of sand and rock

The 2001 documentary Rivers and Tides showcases artist Andy Goldsworthy, who creates ephemeral works of art out of the natural materials around him. Whether it’s leaves, twigs, or icicles, Goldsworthy crafts them into breathtaking constructions that add to the beauty of the landscape while still remaining part of it. Although Goldsworthy invests significant effort in each work, after its completion he leaves it at the mercy of the natural processes of wind, rain, sun, and water, only taking a photo to document its momentary perfection.

Some of Goldsworthy’s most arresting works are the ones he creates out of stone. The film follows the progress of a few such projects, including one in which he creates an egg-shaped structure out of split pieces of stone, and another where he works with stonemasons to create a long serpentine wall in a park in New York state. While the wall is meant to be a permanent installment, the egg-shaped structure Goldsworthy creates in the film is destined to be carried away by the rising tide, showing the vulnerability of a material that most people would take to be among the most solid.

Although originally from England, Goldsworthy has lived for many years in southwestern Scotland, finding inspiration for his work in the local landscape. At the other end of the country, in the Orkney Islands off the north coast of Scotland, once lived a people who similarly worked in stone, but whose work has lasted over 5,000 years. Miraculously protected from the elements for millennia, the settlement of Skara Brae is Europe’s best-preserved Neolithic village.

Midden Earth

The ancient settlement of Skara Brae is currently located on the edge of the Bay of Skaill, on the west coast of the largest Orkney island (called the “Mainland”), but at the time of its construction (thought to be around 3100 BCE) it was situated far inland. Over thousands of years extreme erosion brought the coast to Skara Brae’s doorstep, and also created sand dunes that covered it and kept it hidden until relatively recently. In 1850, a severe storm removed some of the grass covering the mound of sand, revealing the existence of Skara Brae to the modern world for the first time. Some excavation work was done on the site at that time, but it was left untouched after 1868.

In 1928 an excavation of the site showed the full extent of the discovery. Skara Brae had remained remarkably intact, providing an incredible glimpse into the daily lives of its ancient inhabitants. Besides the protection of the covering sand, the fact that a lack of wood in the area had forced its builders to use stone instead contributed to Skara Brae’s longevity. Most other Neolithic structures, created out of wood, have not fared as well.

One of the fascinating aspects of Skara Brae is how it was constructed. To shield themselves from the cold, and to provide a stable foundation, the inhabitants of Skara Brae built their homes into a mound of midden, that is, the waste products of their community. While this may seem distasteful, their garbage was most likely similar to modern compost, made up of completely organic materials. Stones were laid on top of this foundation, creating an insulated and weather-resistant structure.

The settlement consists of eight houses connected by covered alleys, which allowed the inhabitants to remain inside during cold weather. Another notable aspect of Skara Brae is that seven of these houses are strikingly similar, with features common to all of them including a central hearth, two stone box beds (meant to be filled with heather), a dresser/shelf, and a waterproof enclosure built into the floor which might have held fish for bait or for eating.

Time and Tide

Because it gives such a clear picture of what life was like for its ancient residents, Skara Brae has become world-renowned, and is part of the “Heart of Neolithic Orkney” UNESCO World Heritage site. While Skara Brae is being maintained and protected as much as is possible, ironically it is now threatened by the wind and water that once helped to preserve it, because of its proximity to Skaill Bay and the fact that it is exposed to the elements. It may have withstood the ravages of time for the last 5,000 years, but like the ephemeral stone sculptures of Andy Goldsworthy, it remains vulnerable to change and the destructive power of nature.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on November 20, 2006.

Image credit: Wknight94 [CC BY-SA 3.0], from Wikimedia Commons


Source: Interesting Thing of the Day